The Baade window, (at the bottom right of the bright star close to the
center of this image), is a region of the Milky Way, in the Sagittarius
constellation, with relatively little interstellar dust along our line
of sight. It is therefore really a unique 'window' through which the
astronomers can observe the Milky Way galactic Bulge, only a few
degrees from the galactic center. The 'line of sight' through this
'window' passes 1800 light year nearby the Milky Way heart. This region
of the sky was named after German astronomer Walter Baade.